Here we go again: prominent climate sceptics gathering together to meet under the welcoming awning of a right-wing, libertarian thinktank. And some people still choose to question the notion that climate scepticism tends to be far more motivated by rigid ideology rather than reasoned objections to the science?

This time the event is being held in Los Angeles and has been organised by a group called the American Freedom Alliance, which claims to be "a non-political, non-partisan movement which promotes, defends and upholds Western values and ideals".

Topics to be debated include: "The Assault on Human Exceptionalism"; "Agenda 21 and the UN Mandate for Social Revolution"; and "Transhumanism, Deep Ecology and Ecocide: How Are Shifting Social Attitudes Re-shaping Our Appreciation of Human Uniqueness?"

That these characters are meeting up once again to thrash out these issues is no great revelation or surprise. After all, they wear their agenda with pride and promulgate it in the media and on the internet week in week out.

What is more surprising, perhaps, is that some of them are happy to accept the invitation of an organisation that has promoted intelligent design and seems to tread a very fine line indeed between fighting "Islamic fascism" and outright Islamophobia. Are these speakers happy – or even aware – of the company they will be keeping this weekend? Is it fair to assume they did their homework on this group before accepting their invitation to be flown to LA to participate in the event?

To understand the motivations of the American Freedom Alliance, it's best to begin with its website where it lays out its mission statement and vision:

The Alliance sponsors conferences, publishes opinions, distributes information and creates networking groups to identify threats to Western civilization and to motivate, educate and unite citizens in support of that cause. The organization promotes networking, activism and education in the following six areas [it only offers five]: The Islamic penetration of Europe; Academic Freedom; Media Bias; Missile Defense; and AFA Programs [including its annual lecture series, the Western Word newsletter and Western Word Radio].The Alliance's conference's programs, publications, websites and networking groups develop tools and strategies to counter ideologies which underly these threats, including radical Islam, moral and cultural relativism, appeasement and excessive emphasis on multiculturalism.The American Freedom Alliance aims to build a national alliance of people of faith and which involves writers, academics and thinkers from around the world, who will join together through seminars, conferences, publications and activist networks, to promote and protect moral values, democracy and freedom.

The American Freedom Alliance is, perhaps, best known for its on-going legal action with the California Science Center over the cancellation of an AFA event to be held at the centre in 2009 at which it intended to screen a "teach the controversy" film called Darwin's Dilemma, which explores the "Mystery of the Cambrian Explosion in Fossil Records". At the time, Avi Davis, executive director and senior fellow of the American Freedom Alliance, said: "New scientific evidence makes it vital that we take a close look at the numerous inherent scientific problems of the Darwinian theory of evolution." The AFA has subsequently fought the case on the grounds of freedom of expression.

But far more controversial than its dabbling in the "evolution v intelligent design" debate is the AFA's stance on Islam. One of the AFA's three fellows is a highly provocative figure called Robert Spencer who has willingly stoked the "Barack Obama is a Muslim" meme, challenged the building of the "Ground Zero mosque", and runs a controversial blog called Jihad Watch.

For example, in 2010, he used his blog to offer his support to the far-right English Defence League: "The EDL is standing up to violent thugs from both the Left and the increasingly assertive Islamic communities in Britain, and they deserve the support of all free people."

The AFA's funding is unclear, but tax returns (pdf) for the Fairbrook Foundation - a charitable foundation set up by computing multi-millionaires Aubrey and Joyce Chernick, which supports a wide range of Jewish and pro-Israeli groups - show that the foundation has donated more than $100,000 to the AFA since it was founded in 2007. It has also directly funded Spencer's Jihad Watch, too. (A Politico investigation last year showed how the Fairbrook Foundation has funded the David Horowitz Freedom Center, which itself has funnelled nearly $1m to Jihad Watch in recent years. Tax returns (pdf) for the David Horowitz Freedom Center also show that it paid Spencer a salary of $131,981 in 2009.)

That the AFA's "Green Tyranny" event is being held on the UCLA campus might appear to give it the veneer of academic acceptability, or even endorsement. But a UCLA spokesman told me that, while the campus "strives to promote the free and open exchange of ideas in an environment of civility and respect, the presence of an event on campus does not imply an endorsement of the sponsor or the viewpoints expressed". He added: "In the case of this event, it is being held at the Faculty Center, a private club on campus operated by the Faculty Center Association, which is independent of the university."

So, my central question is simply this: are these climate sceptics - particularly ones such as Peiser and Lindzen who like to position themselves away from the fringes as mainstream speakers for their cause - proud to be speaking under the banner of this organisation?